The current study was carried out to study the effect of plant growth promoting rhizobacteria (PGPR) on growth performance of tomato. Azotobacter chroococcum and Bacillus megaterium var. phosphaticum were used in this research. Obtained results showed that A. chroococcum and B. megaterium var. phosphaticum gave high suppression against tomato roots pathogenic fungi i.e. Fusarium oxysporum f.sp. lycopersici and Fusarium solani. In vitro, clear zones around PGPR growth were showed . Such clear zones are likely to be due to the production of antibiotics-like substances, siderophores and cyanogens by PGPR strains. Tomato inoculation with the mixture of A. chroococcum and B. megaterium var. phosphaticum appeared lower percentage of infected plants than those inoculated with them individually. Growth characteristics, macro-nutrients content, endogenous phytohormones and photosynthetic pigments of tomato were significantly increased in the inoculated treatments with PGPR mixture compared by that inoculated with either A. chroococcum or B. megaterium var. phosphaticum singly.
Key words: PGPR, Growth characteristics, macro-nutrients, endogenous phytohormones,
photosynthetic pigments. |